PE Day 4: Nuclear Waste Management

Type of wastes; HLW, LLW, Class A, B, C, GTCC(Greater than class C), TRU
Radioactive decay law; probability that a given nucleus will decay per unit time is called the decay constant, ramda (time^-1). It is independent of the age of the nuclei.
The number of nuclei in the mass is given by: N = m * Na / A
The number of nuclei decreases with time due to decay as given by: -dN(t)/dt = ramda * N(t)
The number of nuclei present at any time is: N(t) = N(0) exp(-ramda * t)
Half time = 0.693 / ramda
The number of nuclei decaying per unit time is the activity, A(t): A(t) = ramda * N(t) = ramda * N(0) * exp(-ramda * t) = A(0) * exp(-ramda * t)
Units of activity are: Becquerel (Bq) = 1 decay / sec or 1 dps
Curie (Ci) = 3.7e10 decay/sec
Specific Activity (SA)
Solid: SA = Activity / Mass [Bq/kg or Ci/kg]
Gases: SA = Activity / Volume [Bq/m3 or Ci/cc]
SA of Radium 226 is 3.7e10 Bq/g = 1 Ci/g

To be continued...